Golf ball



Deu 17, 1940 J.-R. GAMME-ran 2,225,213

GOLF BALL Filed Jan. 27, 1959 INVENToR `OHN R. GAMMETER ATTORNEY Patented Dec. 17, 1940 UNITED STATESl TPATENT OFFICE.v

i i i 2,225,213 l GOLFLBALL-- JohxrR'..Gammete1-, Akron, Ohio Application,January 27,:1939, Serial No. 253,140

1 Claim.

This invention relates to golf balls and the method of making the same.

Heretofore, golf balls have been made, for example, by winding vulcanized thread-rubber on a 5 suitable core, normally a liquid core encased in rubber, to form the ball-center, and then vulcanizing the usual rubber cover about the center. To obtain increased flight when the ball is struck by a club-head, it has been the general practice to wind band or thread-rubber on the core under high tension. As described in the patent to Gammeter, Number 1,167,396, the thread-rubber has been wound on the core under what has been termed super-tension, to obtain even greater increased flight. 'I'his super-tensioned ball-center is obtained for example, by, winding the thread-rubber on the core while stretched nearly to its elastic limit, and allowing the rubber to stand for a number of hours, after which time 2O the rubber in the ball-center becomes somewhat relaxed and may be further stretched beyond the original elastic limit, as by increasing the internal pressure in the liquid core by known methods.

However, it has been found that as the Atension 25 is increased adjacent the surface of the ball-center the tension on the cover also is increased so that the cover tends more readily to split or gash open under the impact of a club-head as when the ball is topped Furthermore, the thread- :i0 rubber being stretched thin provides fewer interstices on the surface of the ball-center into which the material of the outer cover can i'low,during vulcanization to become bonded to the ball-center, and the cover of the nished ball has a great- 35 er tendency to separate from its center.

An object of the invention isto provide an improved, more durable golf ball.

Another object of the invention is to provide a. golf ball which will give maximum ilight upon 40 impact with a club-head.

Another object of the invention is to provide a golf ball in which the tendency of the cover thereof to split under impact with a `club-head is materially minimized.

45 Another object of the invention is to provide an improved golf ball in which the outer cover is thoroughly bonded to the ball-center.

These and other objects will be manifest from the following brief description and the accom- 50 panying drawing.

Of the accompanying drawing:

Figure 1 is a View, partly broken away and in section, o fn a golf ball center in one stage of forming ,the same in 'accordance with the process em- 55 bodying the invention.

`pounded rubber.

Il, such as water, honey, glue, paste, etc., the

fluid being retained in an outer spherical casing l2, of compounded vulcanized rubber, which may be lined with a self-sealing layer I3 of uncom- Thread-rubber or rubber tape 15 l5, stretched substantially to the elastic limit is wound on the core l0. The degree of tension can be adjusted, however, so as to minimize breakage of the thread. When the thread-rubber has been l wound up to about half or iive-eighths of the nished thickness of the wound portion of the ball,

the partially wound center isallowed to stand for a number of hours. It has. been found that. by doing' this for about ten hours, for example, the wound rubber relaxes considerably so that it may afterwards be further stretched a considerable amount. This has often been referred to as supertensioning f This super-tensioning may be obtained, as best shown in Figure 2, by inserting a hypodermicneedle IB, attached to suitable apparatus of known type (not shown), to project into the liquid Il in core l0, and injection of more fluid under pressure to expand the core, and thereby` further to stretch the thread-rubber l5 vsubstan- 35 ltially to its elastic limit. The super-tensioning process may be repeated if desirable or necessary, but according to the present invention thisfs'upertensioning is done on a partly wound ball.'

With the inner portion of the ball thus` under 40 super-tension, thread-rubber is now woundy on the partially wound center under ordinary tension to form an outer layer I8, (see Figure 3) after which a cover I9 of balata, gutta-percha, rubber or the like may be formed about the completed center in the usual manner to form the finished golf ball, illustrated in Figure 4.

It is a well known principle that the night of a golf ball is caused by distortion of the ball upony impact with a club head, and by the ability of the ball to return to normal spherical shape while still in contact with the face of the club. For that reason Vthe wound center should be as hard as possible to produce maximum resiliency and resistivity. However, as before stated, if the center is too hard at the outer regions thereof, there i will be less `distortion under impact and the coverwill be under such tensionas to be readily gashed or split. by the internal pressure ofthe center particularly when theball is toppedfil Golf balls made in accordance with the presen invention, because the tensioning of the threadrubber in` the ball-center is graduated, so as to be( more deformable,` elastic or resilientynearthe cover, `possess the quality of producingflong ight upon impact with a club head, butbecause the outer regions of the lcoreaare substantially not under internal pressure, the coverlS is not under n such tension that it wi1l`readily gashzor `split when hit by a club head. `In addition, the outer layer of the less-tight winding I8 morer eiectively bonds with the cover when `the `cover is i formed about the ball. n n n i n Modifications of` the invention may be resorted to without departing `from the `spirit thereof` or the scope of the appendedy claim. 1

What isclaimedis:l i I A golf ball, comprising a hollow core containing a mobile or, liquidsubstance under high pressure,

a layer of thread-rubber windings adjacentsaid core, the windings in said layer being under high tension, `a layer .of thread-rubber` windings about saidfrstnarried` windings; fthe windings in said last-named layer being stretched to a substantially lesser degreefandsa coverapplied on the ball center comprising said core and lwndings,

`said cover `being bondeddirectly to said lastnamed layer of `windings and being under rele.- tvely low tension about `said ball center.

i JOHN R. GAMMETER. 

